Large closed vessels and tanks such as those used in ships and in the brewery industry require periodic cleaning. This cleaning has generally been accomplished by providing a cleaning apparatus secured to the vessel which comprises a retractable spraying mechanism that enters the vessel through an access door. Typically, these devices are operated by a hydraulic system which is relatively expensive to manufacture, install, repair, and maintain. For effective and efficient cleaning, it is important to properly position the spray means within the vessel. With these prior art hydraulic systems it is very difficult to precisely locate the spray nozzle at a given position. Further, such devices have been limited in the positions for placement of the spray nozzle. Additionally, these type cleaning devices are designed to be used with head pressures of 150 psi or higher and in some applications a head pressure of 1000 psi or higher may be used. As a result of these high pressures, the strength and weight of such prior art devices have been increased to accomodate the forces developed. This has resulted in increased costs to manufacture.
Applicants have invented an improved cleaning apparatus that is simple in operation, reliable in performance, relatively light-weight in construction, and relative low cost to manufacture. Additionally, means are provided for accurately extending and positioning the spray means within the vessel at any desired position and which is capable of withstanding the reaction forces developed during spraying.